Some of conventional imaging devices such as digital still cameras have a function to shoot a plurality of images continuously, and a function to generate a still image by synthesizing parts of the continuously shot images. For example, Patent Document 1 identified below discloses a method of generating a still image with a shutter speed that is different from a shutter speed at the time of the shooting, by storing the continuously shot images in a temporary buffer, and synthesizing parts of the images stored in the temporary buffer.
In the imaging device disclosed in Patent Document 1, when a shutter is pressed in the continuous shooting mode, a predetermined number of images are shot continuously at set intervals, and the shot images are stored in a buffer provided in a DRAM (Dynamic Random Access Memory) which temporarily stores images in a time series. The imaging device stores the continuously shot images in the buffer, and immediately after the continuous shooting ends, starts the synthesizing process to generate a synthesized image, and stores the generated synthesized image. In the synthesizing process, a synthesized image to be stored is generated in accordance with instructions of the user, such as an instruction for changing the number of images to be synthesized.
As described above, in a conventional imaging device, when a shutter is pressed in the continuous shooting mode, a predetermined number of images are shot continuously, and immediately after the continuous shooting ends, the synthesizing process is started, and the generated synthesized image (still image) is stored.
The structure makes it possible to generate a still image with a shutter speed that is different from a shutter speed at the time of the continuous shooting, and to obtain, from desired images in the continuously shot images, an image that is equivalent to a still image shot at a desired shutter speed.
Patent Document 1: Japanese Patent Application Publication No. 2005-86228